This invention relates to laser devices for medical and cosmetic procedures and more particularly to such devices utilizing a tunable and/or fiber laser as a radiation source.
Laser and other optical radiation sources are utilized in devices for performing a variety of dermatology and other medical/cosmetic procedures. Such procedures typically target a chromophore in the tissue of the individual being treated which, depending on the procedure, may be melanin, hemoglobin, lipid, water, pigment of a tattoo etc. Since water is the major constituent of cells in an individual""s skin, water is frequently the chromophore of choice in performing such procedures.
Water being highly absorbent at many optical radiation wavelengths, particularly wavelengths over about 1800 nm, can be a very efficient absorber of optical radiation at these and other wavelength bands, therefore permitting a desired procedure, particularly a dermatology procedure, to be performed from a source having relatively low output energy, and thus from a source which is smaller and less expensive than where a chromophore which absorbs less strongly is targeted or where the wavelength utilized is not as strongly absorbed by water. However, the pervasiveness of water in skin means that radiation at wavelengths highly absorbed by water can penetrate at most a few millimeters into a patient""s skin. Some dermatology or other procedures performed by targeting water require deeper penetration.
Heretofore, it has not been possible to obtain optimum efficiency for a laser dermatology or other procedure targeting water at a variety of depths from a single laser device, and in particular, it has not been possible to scan the treatment laser beam in the depth direction during a treatment procedure.
Focus is also an issue in targeting a particular depth, the relatively large spot sizes of existing devices making it difficult to focus to a precise 3D spot. In addition, some desirable wavelengths are difficult and/or expensive to achieve with existing lasers.
An improved treatment device with a smaller, more easily focused spot size is therefore desirable, as is such a device permitting a range of wavelengths to be easily and controllably achieved so as to facilitate a desired depth of penetration while achieving optimum radiation absorption, and more efficient treatment at the desired depth. An ability to scan in the depth direction is also desirable.
In accordance with the above, the invention provides a device and a method for performing radiation treatment on a patient. The device may include at least one fiber laser and a mechanism for delivering radiation from the at least one fiber laser to the patient. Where the fiber laser is tunable, the device may also include controls for tuning the fiber laser to a desired wavelength. The desired wavelength may be selected a desired depth of penetration in the patient and/or a selected laser efficiency. The controls may also scan radiation depth by the controls scanning the laser wavelength. The controls, which may be either manually or computer controlled, may also change absorption, and thus target heating, by changing wavelength.
A plurality of the fiber lasers may be adjacent mounted to provide radiation along a line, and the lasers may be spaced to achieve selected spaced areas of damage in a target region. For selected embodiments, the tunable range is at least 1800 to 1920 nm. For some embodiments, the device includes a box containing part of the at least one fiber laser along with drivers and controls therefore, a handpiece containing an end of the at least one fiber laser and optics which are at least part of the mechanism for delivering radiation from the fiber laser to the patient, and an umbilical through which the at least one fiber laser passes from the box to the handpiece. The box may also include a mechanism for tuning the wavelength of the fiber laser(s). For other embodiments, the device is a substantially self-contained handheld device containing the at least one fiber laser, a driver mechanism and a control mechanism therefore, and optics which form at least part of the mechanism for delivering radiation from the fiber laser to the patient. For these embodiments, the control mechanism preferably includes a mechanism for tuning the wavelength of the fiber laser(s).
The method includes providing at least one fiber laser, and delivering optical radiation from the at least one fiber laser to a portion of a patient""s body undergoing treatment. The step of tuning the fiber laser(s) to a desired wavelength, either before or during the delivery step, is also preferably provided. The wavelength may also be scanned during the delivery step, thereby causing depth of penetration to be scanned.
The method and device are preferably used to perform a dermatology procedure, and in particular may be utilized to treat at least one of vascular lesions, non-uniformity of skin pigmentation, unwanted hair, acne, tattoos, nail cosmetics and disorders, skin micro-preparation/micro-perforation, improving skin appearance/texture, vitiligo, psoriasis and tissue welding. The method and device may also be implemented using any suitable tunable laser.
The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings, the same or similar reference numerals being used for common elements in the various figures.